Feeding ecology and diet

Finches mostly eat seeds, grains, and other vegetable matter, often supplemented by insects and other small invertebrates. Many species forage on the ground, while others feed mainly on tree seeds. Chaffinches are particularly insectivorous when feeding their young, which receive little plant food until they are fledged. All finches have a strong beak used to crush seeds so the edible kernel can be extracted and eaten. To do this, the seed is wedged against a special groove at the side of the palate, and then crushed by raising the lower jaw. The shell is then removed with the aid of the tongue, and the edible kernel is swallowed. The beaks of finches vary greatly, however, depending on the kinds of foods they specialize on. The crossed points of the beak of crossbills enables them to extract seeds from the cones of conifers; they hardly feed on anything else. The beak of goldfinches is long and narrow enough to reach the seeds of the teasel, which lie at the base of a rigid tubular structure. Hawfinches have a particularly stout beak, used to feed on the pits of cherries and rose-hips.

0 0

Post a comment